Grinding wheel truing apparatus



c. c. ALvoRD ET AL 2,303,715

GRINDING WHEEL TRUING APPARATUS Dec. 1, 1942.

Filed Feb. l2, 1941 2 Sheets-Sheet l EHHHL 55 C A L VURD CH/Cn. LIF/ VEP/'H5 Dec; 1, 1942. c. c. ALvoRD ET AL GRINDING WHEEL TRUING APPARATUS- 2 Sheets-Sheet 2 Filed Feb. l2, 1941 CH/#HL E5 CA VQ/QD CHRL S/' L. VERRE @aten-lieti @ed i, i942 unirse.' srarss 2,303,715 amonio WHEEL TRUING APPARATUS Application February 12, 1941, Serial No. 378,616

1 Claim.v (Cl. 125-11) The invention relates to grinding machines, and more particularly to a grinding wheel truing apparatus for truing a radius or curved face on the periphery of a grinding wheel.

One object of the invention is to provide a simple and thoroughly practical radial truing device for a grinding machine. Another object of the invention is to provide a radial truing' device which is arranged to be readily moved to and from an operative position. Another object of the invention is to provide a radial truing apparatus which is rotatably supported on a grinding machine footstock. A further object of the invention is to provide an improved radial truing apparatus including a semi-circular or arcuateshaped slideway having a truing tool supporting slide supported thereon. Other objects will be in part obvious or in part pointedout hereinafter.

The invention accordingly consists in the features of construction, combinations of elements. and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and

the scope of the application of which will be indicated in the following claim.

In the accompanying drawings, in which is shown one of the various possible embodiments of the mechanical features of this invention,

Fig. l is a fragmentary plan view of the improved radial grinding wheel truing device, shown in operative position on a grinding machine;

Fig. 2 is a cross-sectional View taken approximately on the line 2-2 of Fig. 1;

Fig. 3 is a fragmentary detail view, taken approximately on the line 3-3 of Fig. 1';

Fig/1 is a fragmentary sectional view, on an enlarged scale, through one of the anti-frictionV rollers which support the truing tool slide; and

Fig. 5 is a fragmentary cross-sectional View, taken approximately on the line 5-5 of Fig. 4.

Fragments of a cylindrical type grinding machine have been illustrated in the drawings, comprising a footstock l which serves as a support for the truing apparatus to be hereinafter described. A transversely movable wheel slide II, which may be any of the old and well known types, rotatably-supports a wheel spindle I2 which in turn serves as a support for a grinding wheel i3.

A truing apparatus supporting frame I5 is provided with a cylindrical hole or aperture I6 (Fig.

2) which mates with a cylindrical surface |`I formed on the fcotstock IIJ. The frame I5 is provided with a radial slot I8. A clamping device is provided for clamping the frame I5 in either an operative or inoperative position. This clamping device comprises a hand wheel which is mounted on the upper end of a rotatable shaft 2|. A reduced portion 22 of the shaft 2| passes through a clearance hole formed in the frame I5. rl`he lower end of the shaft 2| is provided with a screw threaded portion 23 which is screw threaded into a lug 24 which projects from the frame 5 and extends below the slot I8. It will be readily apparent from the foregoing disclosure that by rotating the hand wheel 20, the frame I5 may be rigidly clamped in adjusted position relative to the footstock I0.

A stop is provided for locating the truing apparatus frame I5 in'the desired operating position.y A bracket 25 is xedly mounted on the footstock Hl. Ther-bracket 25 supports a stop screw 23 which is arranged in the path of a stop abutment 2 formed adjacent to 'and integral with the lug 24 of the frame I5. The stop screw 26 is provided with a lock nut 28 by means of which the screw 26 may beV readily locked in adjusted position. The parts have been shown with thev frame I5 positioned in an operative position. After a truing operation has been completed, the truing apparatus may be readily swung out of an operating position by rotation of the hand Wheel 20 to turn the screw 23 so as to unclamp the frame I5, after which the frame I5 together with the truingv apparatus supported thereby may be swung in a counter-clockwise direction (Fig. 2) so that the truing tool and ap` paratus may be swung to an inoperative position.

The frame I5 is provided with an enlarged integral semi-circular shaped head 30 which serves as a support for a truing tool slide 3|. The head 30 is provided with a pair of opposed V-ways 32 and 33 which are semi-circular in shape and serve to guide the truing tool slide 3| in a semi-circular path. A plurality of anti-friction rollers 34, 35, 36, 3l and 38 are provided to support and guide the slide 3|. The peripheries of the rollers 34, 35, 36, 31 and 38 are provided with curved or spherical faces which engage the V-ways 32 and 33 and serve accurately to guide the truing tool slide 3| in a semi-circular path. The rollers 34, 35', 36, 31 and 38 are mounted on antifriction bearings and are supported by studs 33, 4D, 6|. 42 and 33 which are in turn adjustably supported on the slide 3|. The main portions of the studs 39, Ml, l, l2 and d3 are eccentric relative to their supporting axes to facilitate adjustment of the rollers so that all of the rollers are maintained in the desired operative engagement with their respective V-shaped guidways slide 3| and the V-shaped guideways 32 and An arcuate-shaped sheet metal cover plate d is fastened at its opposite ends to the ends of the arcuate head 312i. A clearance aperture formed in the slide 3|, through which the plate t5 passes. The cover plate 45 serves to enclose the ways 32 and 33 and rollers 313, 35, 36, 3l and tis so that ne grit or foreign material may readily work its way into the bearing surfaces. A pair of stop plates d? and ll (Fig. 1) are fastened to the ends of the head 3| and serve as supports for adjustable stop screws i5 and 5G, respectively, which are arranged to engage the end faces of the slide 3| to limit its arcuate movement as desired.

The truing tool slide 3l is provided with two upwardly extending bosses 5| and 52 which are provided with cylindrical apertures to support a truing tool holder 53 having a diamond truing tool 54 in one of two positions. The end portion of the bosses 5| and 52 are provided with cylindrical apertures to support a truing tool holder 53 having a diamond truing tool 5t in one of two positions. The end portion of the bosses 5| and 52 are provided with slots 55 and 56 which serve as clamping mediums for clamping the truing tool holder 53 in adjusted position on the slide 3l. A binding or clamping screw 57 serves to lock the truing tool 53 in position in the boss 5| and a `clamping screw 5B is arranged to clamp the truing tool when supported within the boss 52.

As shown in Fig. 1 of the drawings, the truing apparatus is set up to true a radius on the lefthand corner or" the abrasive wheel i3, th. the truing tool supporting slide 3| is ,arL` to swing through an arc of 90 degrees se that the truing tool 53 travels through a quarter-circular path to generate a radius of the desired extent on the right-hand corner of the abrasive wheel i3. The truing tool supporting slide 3| is s .an in its extreme left-hand end position with the truing tool 5d at the end of its stroke, ihe slide 3| traverses in a semicircular path to swing the diamond or truing tool 523 from the fuli line position (Fig. 1) into the broken line position 53a, in which position the truing tool holder is shown as 53a and the slide 3i moved so that its right-hand end face is in engagement with the stop screw 50.

It will be readily apparent from the foregoing 'disclosure that the extent of movement of the truing tool slide 3| is governed by the adjustment of the stop screws 49 and 50. The truing tool 54 and its supporting holder 53 are adjustably supportedin the boss 5| and are adjusted so that the distance from the point of the diamond 56` to the axis of movement of the slide 3| is equal 1 l. L on stud Se which is in turn supper en a hraslret 66 formed integral with the head 30. A manually operable hand wheel 6l is rotatably supported on the stud 65 and is fixedly mounted to rotate with pivotally supported on the stud 64 so that it may to the radius it is desired to generate upon the periphery of the grinding wheel i3.

If it ls desired to generate a radius on the right-hand corner of the periphery of the grinding wheel |3 (Fig. 1), the truing tool holder 53 may be adjustably positioned `within the boss 52 so that the slide 3| may swing from the full line position (Fig. 1) in a counterclockwise direction until the slide 3| engages the stop screw 5|?.

A suitable manuallyv operable mechanism for traversing the truing tool slide 3| in its arcuate path is provided. In the preferred construction a rod Gil is pivotally connected to the slide 3| by means of a stud 5|. The rod 60 passes through and is slidably supported in a sleeve t2. The left-hand end of the rodGU is provided with a turn as the slide 3| travels in its arcuate path. The direction of movement of the slide 3| is determined by the direction of manual rotation of the hand wheel 61.

If desired, the slide 3| may be locked in any adjusted position so that after truing a radius on one corner of the wheel, the diamond or truing tool supporting slide 3| may be locked in one end position while a. relative traversing move mentbetween the truing tool and grinding wheel is provided to true the peripheral face adjacent to the radius formed on the grinding wheel. The sleeve 62 is provided with a slot 68 by means of which it may be readily clamped to the rod 60, if desired. A clamping screw 59 passes through a clearance hole in the sleeve 62 on one side of the slot 58 and is screw threaded into the portion on the opposite side of .the slot G8. It will be readily apparent from this disclosure that by tightening the clamping screw 39, the sleeve 62' may be readily locked to the rod 60 to clamp the truing tool slide 3l and the truing tool 5t in any position desired.

The operation of this improved radial truing device is readily apparent from the foregoing disclosure. When it is desired to true the grinding wheel I3, the hand wheel 20 is turned to unclamp the frame i5 and the frame l5 together with the truing apparatus is rotated on the surface il of the footstock ||l until the stop abutment 21 engages the stop screw 26 to position the truing tool 5G in operative relation with the grinding wheel i3. The truing tool holder 53 is positioned either in the supporting boss 5| or the supporting boss 52, depending upon the position of the radius to be produced on the grinding Wheel. The diamond tool holder 53 is positioned axially within the boss so that the diamond 5t is spaced from the am's of movement of the arcuate slide 3l by-a distance equal te the radius it is desired to produce on the grinding wheel face, after which the clamping screw 5l is tightened to lock the truing tool in adjusted position. 'I'he stop screws 3S and 5D are then adjusted to limit the path of movement of the .truing tool 5t, after which the truing apparatus is ready for opera tion. The grinding wheel i3 may then be advanced to bring the periphery of the wheel into operative' engagement with the diamond 5G, and the truing tool slide 3| may then be traversed in its arcuate path by rotation of the manually opierable traverse wheel t?. The diamond 5A may be traversed across the surface of the Wheel E3 as many times as desired to produce the desired and predetermined radius or curved face thereon. After the truing operation has been carried on to the desired extent, the hand wheel 2@ may again be turned to unclamp the bracket I5, and the bracket |5 together with the truing apparatus may then be swung in a counterclockwise direction to swing the truing tool 56 and other parts to an inoperative position so that they are out of rack |53 which meshes with a small gear or pinion i5 the way for the next grinding operation.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be -made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown inthe accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

We claim:

In a grinding machine having a footstock. ay

radial truing apparatus therefor having a. frame rotatably supported on the footstock. a. semi-circular shaped slideway formed on said frame, a truing tool slide supported on said slideway, means to traverse said slide in either direction through an arcuate path as determined by the shape of said slideway, and a'truing tool adjust ably supported in one of two positions on said slide to facilitate truing a radius at either end of the peripheral operative face of a grinding wheel. i

CHARLES C. ALVORD. CARL G. FLYGARE. 

